Identification key to Vietnamese species of sect. Echioglossum.
1a. Inflorescence shorter than leaves, unbranched; sepals about 6 mm long	C. striatum (Rchb.f.) N.E.Br.
1b. Inflorescence longer than leaves, branched; sepals 8.5–15 mm long	2
2a. Lateral sepals ca. 9 mm long; tip of the mid-lobe of the lip projecting into two tails; leaves narrowly lanceolate, about 1–1.5 cm wide	C. birmanicum (Schltr.) Garay
2b. Lateral sepals ca. 14 mm long; tip of the mid-lobe of the lip projecting into a single short tail; leaves narrowly oblong, about 2 cm wide	C. yersinii J. Ponert & Vuong